1. Field of the Invention
The invention relates to an image processing system, and more particularly to a system suitable for generating reference data suitable for scenic image recognition performed by a navigation apparatus, and a vehicle control system that uses the system.
2. Description of the Related Art
In technical field of car navigation, a method in which information obtained from sensors such as a gyro sensor and a geomagnetic sensor is used (an autonomous navigation method), a method in which signals from GPS satellites are used, or the combination of the autonomous navigation method and the method in which signals from GPS satellites are used has been employed as a method of calculating the current position of a vehicle. Further, for example, a position measurement apparatus described in Japanese Patent Application Publication No. 2007-108043 (JP-A-2007-108043) is known as a position measurement apparatus configured to accurately calculate the current position (refer to the paragraphs 0009 to 0013, and FIG. 1). In the position measurement apparatus, first, a tentative current position is obtained using the signals from navigation satellites, and the like. Then, the coordinates of a feature point (a vehicle coordinate system feature point) of a road marking in a coordinate system (a vehicle coordinate system) with respect to the tentative current position are calculated using the captured image of a scene ahead of the vehicle. Then, the current position of the vehicle is calculated using the calculated vehicle coordinate system feature point and the stored coordinates of the feature point of the road marking (i.e., the coordinates shown in the world coordinate system). In the position measurement apparatus, it is possible to accurately calculate the current position, even when the position measured using the signals transmitted from the navigation satellites and/or signals transmitted from various sensors includes an error.
In the technical field of car navigation, for example, Japanese Patent Application Publication No. 2008-298699 (JP-A-2008-298699) (refer to paragraphs 0007 to 0023 and FIG. 9) proposes a technology in which, on the basis of object information including information on the position and the shape of an object whose image is captured by a camera, measurement point information is obtained. The measurement point information includes shape information and position information on a measurement point that is set in advance in accordance with the type of the object. In the technology, image recognition of the measurement point in the object included in image information is performed based on the shape information included in the measurement point information. Then, the vehicle position information is corrected based on the result of the image recognition, and the position information on the measurement point. Japanese Patent Application Publication No. 2008-298699 (JP-A-2008-298699) also proposes a technology in which the travel of the vehicle is controlled based on the corrected vehicle position information. According to the technology, it is possible to correct the vehicle position information using the result of the image recognition of the object, and to control the travel of the vehicle based on the corrected vehicle position information, when the vehicle is traveling on an expressway where there are not many objects to be recognized, such as an intersection symbol.